Abstract - Supplement While little is known about the impact of host genetic factors on the risk for infection, morbidity and mortality in COVID-19, current epidemiology reveals wide variation in disease course among confirmed cases of infection that is not fully explained by known comorbidities and other risk factors. Because of its pivotal role in the immune response and long-established associations with disease phenotypes, Human Leukocyte Antigen (HLA) variation will likely be found to play a key role in COVID-19 outcomes. Understanding the role of HLA variation will provide important insights relevant to the immunopathogenesis of COVID-19, while also informing vaccine development and potential immunotherapies (e.g. T-cell based therapies). Because the complexity and extreme polymorphism of the HLA region make consolidation, equivalency, analysis, and biological interpretation of HLA data challenging, it is our view that a centralized resource that aggregates data from disparate sources and platforms and provides well-curated bioinformatics and analytical tools will serve to accelerate discovery. Under the parent grant we continue to develop a suite of tools and programs for the standardized analysis, collection, exchange and storage of immunogenetic data, and these tools are being widely adopted by the immunogenetics community. This supplement request will allow us to apply these tools toward the development and application of a pair of web resources. The first will centralize access to COVID-19-related HLA data and HLA data- management and analysis tools, creating a knowledge base and technical resource for HLA and immunogenetics research on the COVID-19 pandemic. As an initial step in advancing this vision, we have launched the hlacovid19.org website. The second resource will connect COVID-19 researchers and clinicians in need of HLA typing services with the immunogenetics laboratories that can provide them. As an early step toward this goal, we have formed the COVID-19 HLA & Immunogenetics Consortium to unite the global community of HLA and immunogenetics experts and leaders in support of these efforts, and harness the collective experience and expertise of the HLA and immunogenetics community as part of the global effort to combat this pandemic.